Motor-control system.



J. A. SEEDEx MOTOR CONTROL SYSTEM.

APPLIQATION FILED 001327, 1908.

1 ,O27,1 59. Patented May 21, 1912.

c which is preferably a winding in series with the load. The winding 0 is only connected in circuit when the machine A acts as a generator, and when so connected in circuit produces a field which is in the same .direction as the field produced by the shunt winding (4, but is opposechto the field produced by the series winding Z1 underthese conditions.

The generator D has a field winding d which is in series with the armature A of the flywheel motor, and also a field winding 6. The winding 6, the arn'iature of genera,- tor D, and the winding a of the motor are all in series. This winding 6, being in series with the shunt winding u, always produces a field in the same direction which assists the field. produced by winding (Z when machine A. is 'acting as a motor and opposes the field produced by winding machine A acts as a generator. .The wind ing (-2 has a small number of ampere turns in proportion to wii'iding (Z.

The relay B has an actuating coil in,

series with one of the supply lines, and is situated. between the flywheel motor and the load. The. coilf is provided with taps moonnected to segments /L. The torque motor E has its armature in series with the actuating coil of the relay and is arranged to turn the drum Jr. a shunt ,winding Z, but it is evident that this field winding may-he connected in the circoil. in any other well known manner. 'lhe flexible cord in is wound about the drum 7c, to which one end is attached, passes over the pulley a and has its other end attached to the arm 'o. This arm is arranged to connect the segn'icuts /L to the contact 7). The dash-pot l!" is attached to the arm 0 and prevents too rapid fluctuations thereof. The cylinder of the dash pot is provided with a stop cocl; F by which the operation. of the dash pot is regulated. l\"hcu the current passing through the armature of motor E exerts a torque suflicicnt to turn the motor, it rotates the drum Ar, winds the cord m about it and lifts the arm o.- As the arm moves upward, different taps of, the winding oi. the relay are connected to the contact 7/, leaving less of the coil) in series with the line. However, as it moves quvard it engages the first of thewveights 1 which adds to the counter torque of the motor Fa As each segment h is passed a new weight is added, and in order to ovcrcomc'the increased .countcr torque, at greater amount of current; must pass through the tli'liiz'it-lll'o of motor i. Fig. 2 shows the method 01'' con ncctin g the weights (7 together by'means of rivets r, so that; they may he lifted up one at,

a time by the urine.

Current is supplied to the lines ii and L lrom some suitable source of direct; current. When thc conditions of the system d, When the I have shown the motor E with 'sifating an :incrcase in its excitation.

are such that the average value of the current taken by the load is not sutlicient to turn the torque motor E, then the whole coil f of the relay is incircuit. It the load is below this average value,'suflicient current does not flow t l'irough the actuating coil of the relay to make it pull up, the machine A- runs light across the lines as a motor, thetotal load beingsupplied from the lines L and L The relay B is in theposition shown in the drawings, the contacts 8, being closed, and therefore the field winding 0 is short circuited. Since the flywheel motor is running light ittakes a small current from the lines, consequently, a small current flows through the field winding (1, and the voltage generated by i'nachine l) is small but in such a direction as to increase'the impressed voltage across the field winding 4, and therefore, increase the strength of the field produced by this winding. If the load is suddenly increased HlJOVQ tlIlS average value, a heavy current flows through the lines L, and L and through the actuating coil of the relay, the armature if of which pulls up, opens the circuit across the con-I tacf's a, which inserts the winding 0 in series with line L and the loath The insertion of this winding increases the'lield strength of the motor, tends to slow it down. or in other words, increases its counter electromotive force; the flywheel, however, tends to keep the speed up and delivers some of its stored ehergy to the macl'iine A, which now tends to act-as a generator and return energy to the line, the current througl-i its armature being reversed. The insertion of this winding calorie would make the machine develop a very-thigh voltage which would probably injure it. As soon as themachine it starts to, act as a generator, however, the field winding '1) prodlurcs a flux which opposes that l'iroduccd bythe wind ings a andc, and thus reduces the voltage of machine i 1 The direction of. the current in the field winding (l is also reycrsed, therebyreversingthe polarity of inachinc .l), the voltage thereof now reduces that applied to the shunt winding (4 and Still-Further reduces the resultant flux-otmachino A." As the overload continues, the flywheel motor gradually 't'alls in speed and the voltage gem eratcd by the motor tends to decrease, ncces-j In order to increase tl'ie'excitation olf ma chine A, the field wmdmgc is provided,

which has practically a constant excitation" and under thcsevconditions produces a 'flux' opposedxto that producedby winding-(Z, so.

that the effect of the voltage produced by;

machine I) graduallydecreases as its speed falls, the field winding; It has a greater voltage applied across its terminals and the flux produced by it increases, thus lending to licepup the voltage of machine A. When 6 Speed as. a cumulative compound motor with out taking an exress: current fr m the line.

it during" the operation ot'my system the current talien in; the load is increased, the

- current tlowiup through the armature ot' motor l) inoreaaesfflt thi inerea ed current persists t'or any length ot. tune. the motor lu will revolve the drum 1' and more the arm 0 up to the next tap on the roll of the relay,

cutting out a porti n ot the coil. The presenee ot' the dash pot i prevents this occurring with the ordinary load thu-tuations which actuate, the relay ll. the motor '1) does not; ormrate until the average value of the load has inereased. \Vhen the relay has a portion ot' the coil out out a corres ondingly greater tlow'ol' eurrent is necessary to malie its armature pull up. it will, therel'ore, he seen that with every inerease'in the averagre value ot the load. my system will automatieally adjust the relay ll; and the tly wheel motor .i will operate as explained :tlHiYt when the whole of the actuating coil is in series with the line I). When the average value ot the load deeraises more of the coil f is gradually reinserted into the circuit.

tVli'ile l have illustrated in ,'.'invcntion in conneetion with a systenvhaving a, flywheel motor. it is obvious: that. my'invention is equally applieahle to .tlywheel motor generze tor sets. nor is it limited to the specific way that l have shown t'o'r varying the field strength of the motor. and I aim in the ap pended claims to voter such modifications afs well as any other modifications that do not involve a departure t'rom the spirit and seope oi my invention.

llhat I claim as'new and desire to secure lt Letters Patent ot' the "l lulled States, is .1. in a system ot motor control, a motor coupled to a tlywheeh adjustahle means for automatically varying the lield strength of said motor, and a device tor aatonuitieally controlling said means to change itspuljust t inent in proportion to the a verage value 01" the load upon the system.

Q. in a' system of motor eontroll atpmver circuit, a motor, an adjustable relay to tomatically varying the field ut ren tliiot 7 Said Inott n'. and means responsive to eurrent in said circuit for I said relay to change its adjustment.

3. In a system of motor control. a motor coupled to a flywheel, an adjustable electrirally operated device to: automatically vi rying the field strength of said motor, and means for automatically controlling said device to change its adjustment in proportion to the average value of the loadv upon the system.

automatically controlling the overload has; eeased, the armature ol' the I said l. in a system of inotouemiti'ol a power cireuit. a motor coupled to a llyu heel, an adpistahle elwtrieally operated device t'or an tomatu-ally varying the lield strength ot said motor. and means responsive lothe rurrent in said eireuit t'or Zltllt:l|l;tll(;lll eon trolling said deviee to change us aduwtmenl in proportion to the average value of the load upon the system.

5. ln :1 sy tem of motor eontrol. a power cirruit,.a motor eonpled to a llyu'heel. an adjustahle relay t'or automatically varying the field strength ot said motor, sponsive to current in said e1 matically controlling said rel adjustment in proportion tothe average value of the load upon said system.

t. in a system of motor eontrol. a power circuit, a motoreoupled to a flywheel. a relay .t'or autouiatitailly varying the field strength ot said motor, the coil ot said relay being: provided with taps,a1nl means tor automatically eonneeting said eirruit to sucees" sive taps depending upon the ave age value ot' the load upon the system.

7. in a system o'l mot cirenit reuit. for auto strength ot said motor. the coil of said relay heing provided with taps.and means respoin sive to the current. in said eirouit t'or eonnectinp; said eircuit to sueeessive. taps depointingupon the average value of the load upon the system.

8. In a system of motor control. a power cireuit. a motor coupled to a flywheel, a relay tor automatieally 'arying the field strength of said motor, the coil of said relay being provided will in said circuit arranged to connect said cireuit to sueeessive taps of said coil depending upon the a vorag'e 'alue of the load upon the system. 7

E). In a system o'l' motor control, a power eireuit. a motor eoupled to a tlrwheel. a relay for automatically varying the tield strength ol said motor. the coil ot' said relay heme provided with taps, a torque motor in said eireu t arrang tal to eonneet said eironit to suceessive taps ot said eoil. and

means t'or changing the counter torque ol torque motor depending upon the change ot the a verage value of the load upon the s stem.

10. In a system at motor eoutrol, a power eireuit, a motor coupled to a flywheel, a relay for automatically varying the tield strength of said motor, the bein provided with taps a. torque motor in said 'cireuit: arranged to eonneet said cireuit to suceessive taps Oil said coil, and weights arangt-afl to ehange the eounter torque of said torque motor in sthps, as the average value of the load upon the system chi-ingest v and means re- 7 ay to change its or eonli'ohn powera motor coupled to a tlywheel. a relay for nitomatieally varying the lield ll2lpH,21lltl a torque motor coil of said relay 11. In a system of motor control, a motor coupled to a flywheel, a field winding onsaid motor, adjustable means for autonuitically cutting aIdJiel'd winding into and out 0ft circuit, and a second means tor automatically controlling said first-mentioned means to elnnitge its-:uljustment 12. In a system of motor control, a motor coupled to a flywheel, a field winding on said motor, adjustable electrically operated means for :mtomatically: cutting said field wmdmg nto and 'out 0t circuit, and a rte-- vice tor autonmtically controlling said means to change its :uljustment in proportion to th arerae'e value ol the load upon the system.

13; In a system of motor control, a power ctrcu1t .a motor coupled'to a flywheel. a field windingon said motor. an :uljustahle relay vtor cutting said field winding into and out. of circuit, and means responsive to current in said circuit for automatically controlling said relay to change its adjustment.

ll. In a system ot motor chntrol. a power tll'tttlll, a motor coupled to a flywheel, afield winding on said motor. a relay tor cutting said field winding into and out of circuit,- the coils ot'said relay heiun'proruledwith it In a system oi motor control, a power circuil. a motor coupled to allywhecl. afield winding on said motor. a relay for cutting, said lield winding into and out of circuit." the coil of vsaid relay heme"provided with laps. a torque motor insaid circuit arranged to connect said circuit to successive taps 0t? 7 said coil. and means tor changing the counteiu tot-due of; said torque mo'tor; depending v upon the change of the average talue ot' the load upon thesystenr; 7

17. la a s 'stem ot' motor control, a power tircuil, a. motor (oupled to a ll-ywheel, afield winding o'n said motor, arclay for cutting said lield winding"- into and out of circuit, the coil or said relay being provided with ta is, a torque motor in said circuit arranged to connect Silld vil'C/tlliw to succes ive taps ot said coil, and weights arranged to change the counter torque of said torquemotor in steps, as the average value ol: the load" upon the-system changes.

IS. in a system of motor ctmti'ohr flyflitltj'l ItiOiQl', a field 'wmdingnn said motor,

'meansresponsive to the loadon said sy' 'sultant field'heing arranged to a relay for cutting" and means responsive to the ioad on said system for cutting said field winding into and out, of circuit.

1.9. In a system of motor control, a flywheel motor a field winding on said motor, and an electrically operated device for automatically cutting said field winding into and cut 0 1? circuit.

20. In a system of motor control, a fiy-t wheel motor, a field winding on said motor, an electrically operated device for automatr cally cutting said field winding'into and out of circuit. and means for decreasing the resultant field of said motor so that when said motor acts as a generator its voltage does not become excessive.

Qt. la a. system of motor control, a flywheel motor, a fieid winding on said motor, means responsive to the ion 1 on said system for cutting said fieldwinding intoeircnit, and means for decreasingthe resultant field of said motor when said motor acts as a generator so that its voltage does not beconic excessive. V

22. In a system of motor control, a flywheel motor-,a field windingon said motor, em for cutting said field winding? into circuit,

and means for decreasing the resultant field of said motor when said motor acts as a generator so that its voltage does notbecome excessive. said means for reducing the rereduce its own effect; as said motor falls in speed.

2;). In a system of motor control a flywheel motor; a field .winding' on said motor, means responsireto' the load on said system l'or cut-titre said field winding into and out of circuit:. a shunt field winding on aidmotor,.and an exciter arranged to decrease the resultant field of said motor when said motor acts as a generator.

"it. In a system of motor control, a flywheelmotor. a field winding on said motor, -meansresponsive to the load on said system for cutting out; of circuit. a shuntfield winding onsaid field winding into and said nuitor. and an citciter arranged in said shunt field winding circuit 'lor decreasing i the resultai'itficld ol. said motor when Said motorfacts as'a gcneratmx I 25; in as \"stem. ot motor 'control. a fly-- wheclniot or. a, field winding jou said motor,

out ol circuit. a shunt field winding on said inott-n'f and an excitcr having its armature in series with said'shunt field winding.

23th In a'svstem 'ot' n'iotor control, a fiywhee] motor, a jtield winding on said motor, means responsive to thc load oxi'saidsys: tcml'nr cutt-i wsaid field winding-into and cut otW-ircuitfa shunt field whaling 011 said motor, and aneaciter having its armature in sericsiwithsaid shunt field winding, sa d aneaus responsire to the loitd on said s v,s, lem't'or cutting said field winding into and exciter being arranged to reduce the voitage supplied said shunt winding when said flywheel motor acts as a generator.

27. In a system of motor control, av flywheel motor, a field winding on saidmotor, means responsive to the load on said tem for cutting said field winding into and out of circuit, a shunt field winding on said motor, and an exciter having its arn'iature in series with said shunt field Winding and its field winding in series with the armature oi the flywheel motor, said exciter being arranged to reduce the voltage supplied said shunt winding when said motor acts as a generator.

28. In a system of motor control, a flywheel motor, a field windingtin said motor, means responsive to the load on said system for cutting said field winding into and out. of circuit, a series field winding on said motor, a shunt field winding also on said motor, and an exciter having its armature in series with said shunt field winding, said exeiter being arranged to reduce the voltage supplied said shunt field winding when said flywheel motor acts as a generator.

29. In a'system of motor control, a flywheel motor, a field winding on said motor, means responsive to the load on said tom for cutting said field winding into and out of circuit, a series field winding on said motor, a shunt field winding also on said motor, and an exeiter having its armature in series with said shunt field winding. said we citer and saidseries field being arranged to decrease the resultant field ot said motor when said motor acts as a generator.

30.111 a system of motor control, a livwheel motor, a field winding on said motor,

means responsive lothe load on said system forcutting said field winding into and out of circuit, a series field winding on said motor, a shunt field also on said motor, and an excitcr having it armature in series with said shunt field winding and its field winding in series with the armature ol' the livwheel motor, said exciter and said series field being arranged to reduce the resultant field of said motor when said motor acts as a generator.

31. In a system of motor control. a flywheel motor. a field winding on said motor, an electrically operated device for cutting said field winding into and out. of circuit, a series field winding on aid motor. a shunt ticld winding al o on said motor, and an exritcr having its armature in series with said .lnmt field winding and its field winding in series with the armature ot the tlvwhecl motor, said exciter and said series field being arranged to reduce theresultantfield olfsaid motor when said motor acts as a genorator.

32. in combination, a power circuit, a dynamo electric machine, a regulating device tln-rc'l'or. a torque motor in said circuit arranged to operate said device and weights arranged to change the contiter-torque of said torque motor in steps as the average value of the load upon the circuit changes.

:33. in ron'ihination, a power circuit, an

adjustable relay therein, a torque motor in said circuit arranged to control said relay to change its adjustment, the torque of said motor varying with the load on said circuit, and means tor changing the eounter torque ol said torque motor, as the torque motor rotates in response to changcs in the average value. ol' the load upon the rircuit.

ti t. in -i ()ll)lllllzlll()ll, a power circuit, an adjustable relay therein, a torque motor in said rirruit arranged to control said relay to ohange its adjustment, and weights arrang d to rhange the counter-torque of said torque motor in steps as the average value of the load upon the circuit changes.

lu \iitnn: whereof. l have hereunto set -lH hand this .L llh dav ol' Urlohor, 1008.

JOHN SlllllH L i l Inn -ans:

lil'INJAJHN ii. Ilium, llicuix ()nronn. 

